Assightob to chicago



ATTORNEYS Patented Sept. 9, 1919 I INI/ENToR f/AAl y WI. C. HUTCHINSON.

PNEUMATIC TOOL HANDLE APPLICATION FILED AUG.25. |916.

.I l I :v I l I I I I I l I l I I I I I l I a I I I I I N I I I I I l I I I I I l I wITNEssEs 1MB COLUMNA PLANQGRAPH C0.. WASHlNuToN, n. c,

SON, a citizen of the United States, residing UNITED STATESPATENT OFFICE.

Mon'roN C. HUTCHINsoN, on WOCDBURY, NE

e "JERSEY, AssIeNon rro CHICAGo PNEUMATIC Toon coIvIrANv,` or CHICAGC,` ILLINOIS, A `coiuPoiaA'rIoN 0F NEW JERSEY. e

\ i NnUIvrATICTooL HANDLE.

Application `filed August 25,

To all whom t may concern: t t

Be it known that I, MoRToNsC. HUTCHIN- at Woodbury, in `the county of,` Gloucester, State of New Jersey, have invented a new and useful `Pneumatic-Tool Handle, of which the following is a specification.

My invention relates to` the graspinghan-` dle of a pneumatic tool of the type generally Vflow of the compressed air` or other motive employed for riveting and chipping, ,i and analogous uses, and consists more especially of a novel `construction ofthe valvular mechanism therein,` particularly the bushing, valve and their adjuncts, wherebythe fluid underpressure fromthe supply hose to the toolcylinder is controlled through the medium of a manually operated lever generally commercially constructed, it `has having a bore therethrough or other device "mountedonlthe upper or other portion of the grasping handle. ln pneumatic tools of the prior art as e,

` vantage of being `cheaply manufactured,

since it may be somewhat cheaper to manufacture a bushing having its internal bore of the same diameter throughout and it may also be i somewhat cheaper to construct a throttle valve with two pistons of uniform diameter, I have found that in thesetools,` which are frequently subjected to consider- ,e ablei abuse by the workmen, a throttle valve 1 of this character soon becomes leaky and is` V less eflicient than a throttle valve of my novel construction hereinafterhreferred to,` wherein a valve stem having aground pis` ton thereon is employedin conjunction with g a lower valvebody preferably of greater latter upwardly, the

diameter, which has a relatively looserlt in its bushing to enable a limited volume of live air at reduced pressure to constantly I act on the bottom of the valveto force the` valve seat in thejbush in `being intermediate said `pistdrm valve te y, and said valve may seatingapwamly Specification of Letters Patent.

`191e. serial No. 11ers?.

like where a number of construction, all as will be hereinafter 4fully setfolth. t

1tion,`I have shown tion is not limited to the precise `Bateman septic, 191e.

1 and being alwayspressed `upwardly toward and against its lseat by the pressure of the `motive fluid, the construction being such that `not only is the life of the throttle valve and bushing greatly prolonged, `and leakage` of the compressed lair prevented, but the valve in thehandle `will remainleifectively seated under normal `conditions of non-use orwhen the pneumatic any leakage or waste of the compressed` air being entirely fand absolutelyobviated, this item of leakage` ofthe compressed air` or other motive fluid inlargeindustrial plants such as shipfyards, boiler i shops and the one of considerable "importance"` t It further consists of othernovel features `For thepurpose of illustrating my invenin the accompanying drawings `certain forms thereof which are at present preferred by me, since the same will give in practice satisfactory and reliable results," although it `is `to be understood that thevarious instrumentalities of which my invention consistscan be variously arranged and `organized and that myl inven arrangement and organisationi of these instrumentalities as herein shown and described.`

The ligure represents a vertical sectional view of a pneumatic tool handle, embodying my invention, the valve and its adjuncts be;

ing shown in elevation.` g g `Referring to the drawings e "1 designates a pneumatic toolhandlehavingthe inlet l2, containing the nipple 3, for

the attachment of the" compressed air hose, said air ,or other `fluid pressure passing through thefchamber 4 and inlet ports 5 and outlet ports `6 of the valve bushing 7 to the pressure supply duct 8, located inthe g grasping or" other portion 9 of the handle 1,

andb'eing conducted therefrom to the tool `cylinder l0, which `may be of any suitable construction. u The valve bushing maybe secured in the handle by a driving fit or otherwise. p g

g 12 designates a valve seat in the bushing 7 located interin'ediately oftheinlet ports 5 and outlet ports 6,` against which the throttle valve` body `13 seats in an upward direction,

g said lvulva" havingi the beveled portion la,

ofpneumatic `tools of `this i general characterare employed being tool is inoperative,

f ing normally at all times pressed upwardly against its seat by the pressure of the mowhich acts as the valve proper, the latter be- Vthe valve body ,13 shouldhave about .005

play in the lower portion of its bushing, it being only essentialy that the valve 141 fit accurately upon its seatr12. TheV object in lmaking the; valve body 13 with about .005

play is to enable al limited quantity of the motive fluid -to flow through the port 5 raroundv thevalve 13 and be wiredrawn down into thevalve chamber 29 so that the valve prop'erle will be always tightly seated, so

as :to prevent Vany leakage of the motive v'fluid when the tool'is not yin use. The up-y per extremity 21 ofthe valve stem is in contact with and depressed by the cam 22 of the'manually operated valve lever 23, which is composed of thin metal and pivotally mounted at 24 in the narrow slit 245 in thel l.upper or other portion of the grasping handle, said valve lever being provided at its lower portion. with the kextension 26, which is normally in contact with the shoul- 'f der 27' and at its upper portion with the thumb piece`28, whereby a depression of said Y thumb 'piece will tend to unseat the valveV 14 from its seat 12, saidvalve being nor- :nially held .seated at, all times by a limited quantity of motive fluid wiredrawn to below th'ebottom of said valve to seat the same upwardly ata pressure reduced from the initial pressurek of .theincoming motive fluid through the nip-ple 3.

It willibe apparent that while have shown my-,device in the present instance as applica-ble Yto' the well-known .Boyer7 type of grasping handle `wherein` the pressure lsupply duct is led through the vgrasping portion, .of' thehandle, my, invention is .equally applicableto other formsof pneul. i YLmatic tool handles, kwherein the valve proper as well as the pressure supply duct are located wholly outside ofthe grasping `portion of the handle, it being a Common right Y vto conduct the moti-ve fluid tothe pneumatic tool cylinder' either within Vor without the grasping Vportion of the pneumatic tool n -lflandle-V It will be seen from the foregoing that by making thepiston 19 of aground fit,y there will be no improper leakage of the motive fluid; when the valve body `111 is Ain rits de- Y. pressed; Vposition,fand-vw4hen the valve is closed, which is the positionvitheI parts assume when the tool is not in use, there is no .opportunity for leakage under any conditions. The valve body 13 can obviously be cheaplyl manufactured, it only being essential that the valve proper 141 accurately lit its seat 12.

As already explained, in the old style of throttle valve where the bushing has a bore of uniform diameter and the valve pistons are of uniform diameter, in a few months7 time owing to the wear between said pistons and bushing, there is constant leakage of compressed air which it is especially desirable to prevent on account of the expense and waste involved, and furthermore, during-said waste and leak-age, the motive fluid is permitted to pass to the piston of the tool, frequently causing the latter to accidentally start or ily out of the cylinder, together with the'bushing or river set, which may causeserious injury. It will be readily seen that all these dangers and disadvantages are prevented by my device.

I .desire also to call especial attention to the advantages of my novel construction 'whereby springs fare dispensed with, it being understood that owing to the slight play of .005 between the piston 13 and the lower portion of its bushing, there is constant air pressure always leaking past said piston below it, so as to always press the valve 111 upwardly against its seat.

I have found this construction in practice to be very advantageous, since it not only lessens the cost of manufacture, but, in addition, makes the throttle valve easier to operate, since the workmans thumb can depress thelever 23 more comfortably against 100 the cushion of live motive fluid` than against a' spring, as heretofore generally employed.

It willnow be apparent that I have devised a novel and useful construction of a pneumatic tool handle, which embodies the 105 features of advantage enumerated as desirable in the statement of the invention and the above description, and while I have, in the present instance, shown and described a preferred embodiment thereof which will Y give in practice'satisfactory and reliable results, it is to be understood that the same is. vsusceptible Vof modification in various particulars without departing from the spiritor scope of the invention or sacrificing any of its advantages.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

The combination of a pneumatic tool hanelle having an inlet chamber located at the lower outer portion of said handle and a pressure supply duct leading through the grasping portion thereof, a manually operated valve lever pivotally mounted in a narrow slit in the upper portion of said handle 'and capable of a free and uninterrupted fortherein of greater diameter, a single closure secured within the bottom oit' said bushing, a downwardly facing valve seat being formed at the junction of said bores, and said bushing having an inlet port constantly open to motive fluid in said lower bore and a lateral outlet port in its upper bore respectively, a throttle `valve seating upwardly against said seat, the body of said valve eX- tending below said seat, and fitted in said bushing with a play of about .005 oit' an inch to permit motive fluid to` leak through said constantly open inlet port against said valve body and be wiredrawn downwardly past said Valve to the bottom thereof7 so as to constantly press said valve upwardly against Copies of this patent may be obtained'for ve cents each, by addressing the its seat, the space between said closure and the bottom of said valve being unobstructed, a valve stem extending above and integral with said throttle valve, a piston on said valve stem of less diameter than said valve and having a ground t within said upper bore of said bushing, said piston and valve stem beingI Vconnected to said valve body and adapted to reciprocate in unison therewith, and a cam on said Valve lever in direct oontaot with the top of said valve stem to clepress the latter.

Y MORTON C. HUTOHINSON.

Witnesses:

`Lnon LBUGHWATER, WALTER H. LEEDON.

Commissioner of Patents,

Washington, ZD. C. 

